1. Field of the Invention.
This invention relates to archery and, more particularly, to an arrow rest support which is pulled down by action of the bow limb when the arrow is released.
2. Description of the Related Art.
The shooting of arrows with a bow is a skill practiced by man that dates from prehistoric times. The bow in its various forms was for a long time a principal weapon of war and of hunting throughout the world. Proficiency in the use of the bow involved many of the features associated with a sport--practice to achieve accuracy or increased distance, the development of skill in aiming and releasing the arrow, the element of competition, and the satisfaction of skilled performance under pressure. Although in the 15th century the bow was superseded as a weapon of war, it remained in use as a hunting weapon and for recreational activities. Since that time the activities associated with the bow have evolved into the modern sport of archery. By the 1970s, the total number of participants in all forms of the sport was about 8 million in the United States alone. Of these participants, a relatively small number strive for ever greater distances in "flight" shooting, a much larger number are concerned with accuracy in shooting at targets of various kinds at specified distances, and a still larger number have adopted the bow as their primary weapon for hunting game.
The bow was with little doubt the first mechanical device that allowed the achievement of hurling a projectile with more speed than was possible by throwing. It accomplishes this by storing energy in the bow limbs while the bow string is drawn, keeping it stored during the aiming process, and converting the stored energy during release of the bow string into energy of flight of the arrow. Its invention, thirty thousand or more years ago, easily ranks in importance with the invention of the wheel and the capability of creating fire. Evidence that the bow was known as an effective hunting weapon thousands of years ago is demonstrated by rock paintings in caves in Eastern Spain.
During its protracted history the bow has taken many shapes and sizes and has assumed various structures. Artisan bowyers used their ingenuity to develop variations from the primitive early prototypes. For example, various natural materials such as wood, horn, sinew, gut, and rawhide were found to be especially suited to the purpose of making a device that would enable an arrow to be sent towards its mark at the will and under the control of the archer.
Initially bows were made of one material, usually wood (self bows). Later bows were made of several materials, such as wood, horn, and sinew, glued together in layers (composite bows). Short self bows were used in Europe up until the 11th century. The longbow, originally also a self bow, apparently originated in Wales. Its length was about the same as the height of the archer, and the arrow about half as long. The bow was held with outstretched arm and the arrow drawn to the ear of the bowman.
The limbs of the modern bow are composite and laminated to give exceptional strength in both compression and tension. A long, rigid middle section provides mass and stability which contribute to accuracy; its length compensates for the relatively short limbs, which contributes to the desirable action that is the hallmark of the longbow. The string is as light and strong as possible and is usually made of a synthetic fiber.
From the time of release until the arrow leaves the string, the force exerted on the bow includes one that tends to rotate the bow about an axis parallel to the string, the axis passing through the hand holding the bow. Any rotation of the hand produces a small lateral error in air. Various stabilizing schemes are used to increase the moment of inertia about the axis of rotation referred to, thus lessening the effect of the rotational impulse imparted to the bow when the arrow is released and reducing the lateral dispersion of hits on the target.
The materials used for making arrows must have such desirable characteristics as strength, stiffness, and resilience consistent with minimum weight. Uniformity in the mechanical and elastic properties of the arrow shafts is highly desirable. The stabilizing vanes, traditionally feathers and in modern times plastic fins, are known as the "fletching," and must be the same and attached in the same location and configuration on all the shafts.
Modern target arrows are generally made of metallurgically treated aluminum alloy tubing with close tolerances on diameter and wall thickness. Arrows can be made very closely alike from such tubing. To reduce drag, plastic vanes are usually used, and the surface of the arrow is given as smooth a finish as possible. The plastic fins are cemented onto the shaft in a jig so that they have identical flight characteristics.
The so-called Mediterranean draw is used to draw and loose the arrow. This type of draw is executed by drawing the string with three fingers, the first above and the second and third below the nocked arrow. In right-handed shooting, the arrow rests on an arrow rest on the left side of the bow. Various devices have been designed to aid in drawing and loosing the arrow. They have permitted marked improvement in accuracy.
Various factors related to the manner in which the bow and arrow interact during the small period of time between the release and departure of the arrow from the string affect the subsequent flight of the arrow. One such factor is the collision of the fletching with the arrow rest as the arrow leaves the bow. Any contact between the fletching and the arrow rest can cause a deflection of the arrow from its intended path.
Various types of conventional arrow rests are described in U.S. Pat. Nos. 4,332,232, 3,865,096, 3,935,854, 4,398,528, and 4,489,704.
Two arrow rest holders currently on the market can be described as pull-down or fall-down arrow rest holders. One uses the recoil of the bow to move a small weight to release a spring-loaded device. The arrow rest is forced down and out of the path of the fletching so as not to deflect the arrow from its intended path. This device must be cocked before each shot. The second device has a rubber tube attached to the device and to the bow cables so that when the bow is drawn, the rubber tube pulls the device up into shooting position and when the arrow is fired the arrow rest is allowed to fall. Other such devices may be available, but basically they all use gravity or a spring of some sort to pull them down. Because the arrow moves at about 200 feet per second when the arrow rest begins to fall, it is difficult to find a spring that can move fast enough so that the fletching does not hit the arrow rest as it is being pulled down. Any contact between the fletching and the arrow rest as it is being pulled down results in a deflection of the arrow. In addition to the deficiencies of presently available arrow rest holders of the fall-down or pull-down type with respect to failure to clear the arrow fletching, most of these devices have to be cocked before each shot.